Re: Filter recommendation for DC fan motor interference to echo Link.
I find that grounding plays a role in DC fan noise
suppression; try running the filtered fan power wires straight to the
power supply.
Bob NO6B
At 4/27/2025 12:28 PM, you wrote:
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You could try about a 10 ohm
resistor, with a >2000 uf cap on both sides to ground (A pi network).?
?? Better yet, use a toroid instead of a resistor with a lot of
windings.? ??
Good news is that the noise is rather high in frequency, so it is easy to
eliminate.
I have not ever had to resort to buying a specific fan to remove
the noise.? ?? It always works with a filter.
Put a scope on it to verify that noise is indeed being induced on the DC
line.? ? ?
Andy Zorca
WJ9J
On Sun, Apr 27, 2025 at 12:48?€?PM Chad Nelson via
<chad.nelson71=
charter.net@groups.io> wrote:
- Hi everyone, I just installed a small DC fan to cool my Link radio
and notice when echo Link is active I get a wine on the signal going into
the controller for my echo link. Don't get this when repeater is
transmiting on its own. Any good filter recommendations to
eliminate?? this out?
- Chad Nelson WI9HF/WRPL979
- Janesville Wisconsin
- 608-754-8671
|
Re: Help with out of range programming a Motorola GP300
Ron,
Some HTs will not go much past their designed range as the VCO, transmitter, and receive filters bandwidth is only so wide.
Once programmed, you'll need to run the alignment section of the RSS/CPS software to adjust filters, deviation, etc.
I've got a couple MTX9000 900MHz HTs. Same model. One will do 927MHz TX and RX and 902 TX, while the other will only do 927 RX!
Benjamin, KB9LFZ?
I was recently given a pair of GP300 HTs and am trying to get them reprogrammed for some new hams in the area.
?
I have the programmer and RSS and can download the codeplug.? But, these are 398-443 MHz RX radios (P94YPC20C1) and won't allow me to put the Amateur repeater frequencies in.
?
I've tried the Shift key trick when entering frequencies to no avail (have used this successfully on Radius and GM300 models).? Even tried using a Hex editor and directions I found here to alter the ID bit associated with the model.
?
Neither works.
?
Any thoughts on what to try next?
?
ron
|
?
wow, mine must be an old one, has a pass transister
regulated supply.?
?
Butch Bussen WA0VJR butchb@...irlp
7135 allstar 56023 echolink 790800
----- Original Message -----
Sent: Sunday, April 27, 2025 11:38 AM
Subject: Re: [repeater-builder] Kenwood TKR-820 UHF
Run it off external 12v supply....the internal is a switcher...they
die like that if you haven't recapped it
Weird one for the experts... I have a TKR-820 that has been running for
YEARS.? And before I got it, it was running for years!!!
?
After about of month of running (summer/winter no difference), it kicks
off.? When I reset the power switch, it flashes red briefly and goes
out.? If I leave it off overnight, I can come back in the morning, turn
it on and work for another month...? Really????? How does one
trouble shoot this???
|
UHF
What is new price on them?
Roger
On 4/27/2025 3:09 PM, Chris Boone
WB5ITT via groups.io wrote:
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At least 1500 if not more. Especially since they are
still in production and they're not going anywhere anytime soon.
Try 80% of the new price, that's what I usually use. What band?
What
is the value on the used market for a Motorola SLR5700
repeater
removed from a working trunk system in excellent condition?
Only reason for change is system does not meet the needs of
the user and
a system to meet their needs is being installed.
Hoping to recover some of their investment.
Thank you
Roger
|
At least 1500 if not more. Especially since they are still in production and they're not going anywhere anytime soon. Try 80% of the new price, that's what I usually use. What band?
What is the value on the used market for a Motorola SLR5700 repeater
removed from a working trunk system in excellent condition?
Only reason for change is system does not meet the needs of the user and
a system to meet their needs is being installed.
Hoping to recover some of their investment.
Thank you
Roger
|
Re: Filter recommendation for DC fan motor interference to echo Link.
You could try about a 10 ohm resistor, with a >2000 uf cap on both sides to ground (A pi network).?? Better yet, use a toroid instead of a resistor with a lot of windings.??
Good news is that the noise is rather high in frequency, so it is easy to eliminate.
I have not ever had to resort to buying a specific fan to remove the noise.?? It always works with a filter.
Put a scope on it to verify that noise is indeed being induced on the DC line.???
Andy Zorca WJ9J
Hi everyone, I just installed a small DC fan to cool my Link radio and notice when echo Link is active I get a wine on the signal going into the controller for my echo link. Don't get this when repeater is transmiting on its own. Any good filter recommendations to eliminate? this out?
Chad Nelson WI9HF/WRPL979
Janesville Wisconsin
608-754-8671
Send from my spectrum iPhone 16.
|
What is the value on the used market for a Motorola SLR5700 repeater
removed from a working trunk system in excellent condition?
Only reason for change is system does not meet the needs of the user and
a system to meet their needs is being installed.
Hoping to recover some of their investment.
Thank you
Roger
|
Re: Help with out of range programming a Motorola GP300
They probably won't go. 440 is going to be pushing the upper limit, most likely.
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On 4/27/2025 8:53 AM, Ron via groups.io wrote: Oops, yes typo.? Should have been 433...
I'm trying to get them programmed to local Amateur repeartes in the 441 to 444 MHz receive range with 446-449 matching 5 MHz offset TX.
ron
KA3JIJ
|
And yes, the front end needs to be re-tuned if it's being moved more than maybe a MHz.
But there's also an issue with ceramic filters in the IF on most all radios from that vintage back into the 90's. They just seem fragile...
If you hear squelch noise, but it seems quiet compared to normal, that is likely the problem.
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On 4/26/2025 11:38 PM, Ramesh Dhami \(VA3UV\) via groups.io wrote: On 2025-04-26 11:33 p.m., Mike Sullivan via groups.io wrote:
Got a TKR-850 that was abandoned at a tower site.. powers on and transmits fine (can transmit using CW ID button and getting 25w output) but receive appears deaf, Busy light is staying on and can't key it up with any amount of power. Tried both ham and GMRS frequencies, both exhibit the same behavior. Checked all the usual settings and can't get it to go away. Any ideas of anything else to check before I say she's dead and just plan on using a mobile for receive? <-- Hi Mike:? Have you been able to "read" the repeater using the Kenwood programming software (i.e., to confirm he RX frequency)?
Can you hear anything via the local speaker (you do need the loop-back connector plugged into the 15 pin molex connector / or you can carefully use a jumper wire to enable the front speaker.
Do you have any test equipment (signal generator, RF test set, etc.)?
Ramesh, VA3UV, WA3UV
|
I haven't had a chance to post it, but I have a set of *factory* 47.42 channel elements for a Micor. K1003A/K1004A
They should only go to someone who is actually putting a Micor on 47.42, not someone who will take the rocks out and re-xtal.
And yes, they did work about a year and a half ago. Netted A-OK. It was the rest of the station that didn't.
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On 4/26/2025 6:19 PM, Marlo Montanaro - KA2IRQ via groups.io wrote: I've been tasked by our Red Cross regional director to get a 47 MHz antenna installed for "low band" VHF use on one of their buildings.? It seems to be a difficult band to find commercial antennas for, but the Red Cross is still quite active on the band.
I'm looking at the Andrew DB201-L.? But everything I find about it is years old and I'm having trouble finding a source to purchase one.
Is it still manufactured?? And if so, where can I purchase one?? If not, is there a newer/better alternative before we just build a ground plane antenna (I'd rather not have to, to be honest).
I know this isn't strictly repeater related, but I've found other topics on this specific antenna in this forum (although quite old).
Thanks!
73,
Marlo
KA2IRQ
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Re: Filter recommendation for DC fan motor interference to echo Link.
Hello Mike,
Happen to have a part number to start a search with? Google shows a lot of bathroom exhaust fans.
Mick - W7CAT
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----- Original Message ----- From: "Mike Besemer - WM4B via groups.io" To: repeater-builder@groups.io Sent: Sunday, April 27, 2025 11:25:31 AM Subject: Re: [repeater-builder] Filter recommendation for DC fan motor interference to echo Link. Google Panasonic low EMI fan.? They work great; no noise.? I run them exclusively on several repeaters. Mike?WM4B
Yahoo Mail: Search, Organize, Conquer
On Sun, Apr 27, 2025 at 1:13 PM, Teton Amateur Radio Repeater Association (TARRA)wrote: The problem is your fan of course. I looked and can't find my information on it, but someone on here will probably have it. Panasonic
make a line of fans that won't make electrical noise. I have fans for
cooling one of my GM300 radios. It made noise. I tried everything,
including running the fans on a battery, still had the noise. Just
getting induced in the air. Finally I decided rather than to fight it,
that I know when the fans come on and are working.
Mick - W7CAT
----- Original Message -----
From: "Chad Nelson"
To: repeater-builder@groups.io
Sent: Sunday, April 27, 2025 10:47:58 AM
Subject: [repeater-builder] Filter recommendation for DC fan motor
interference to echo Link.
Hi everyone, I just installed a small DC fan to cool my Link radio and notice when echo Link is active I get a wine on the signal going
into the controller for my echo link. Don't get this when repeater is
transmiting on its own. Any good filter recommendations to eliminate
this out?
Chad Nelson WI9HF/WRPL979
Janesville Wisconsin
608-754-8671
Send from my spectrum iPhone 16.
--
Untitled Document
-- Untitled Document
|
Run it off external 12v supply....the internal is a switcher...they die like that if you haven't recapped it
Weird one for the experts... I have a TKR-820 that has been running for YEARS.? And before I got it, it was running for years!!!
?
After about of month of running (summer/winter no difference), it kicks off.? When I reset the power switch, it flashes red briefly and goes out.? If I leave it off overnight, I can come back in the morning, turn it on and work for another month...? Really????? How does one trouble shoot this???
|
Weird one for the experts... I have a TKR-820 that has been running for YEARS.? And before I got it, it was running for years!!!
?
After about of month of running (summer/winter no difference), it kicks off.? When I reset the power switch, it flashes red briefly and goes out.? If I leave it off overnight, I can come back in the morning, turn it on and work for another month...? Really????? How does one trouble shoot this???
|
Re: Filter recommendation for DC fan motor interference to echo Link.
Google Panasonic low EMI fan.? They work great; no noise.? I run them exclusively on several repeaters.
Mike?
On Sun, Apr 27, 2025 at 1:13 PM, Teton Amateur Radio Repeater Association (TARRA) <tarra@...> wrote: The problem is your fan of course. I looked and can't find my
information on it, but someone on here will probably have it. Panasonic
make a line of fans that won't make electrical noise. I have fans for
cooling one of my GM300 radios. It made noise. I tried everything,
including running the fans on a battery, still had the noise. Just
getting induced in the air. Finally I decided rather than to fight it,
that I know when the fans come on and are working.
Mick - W7CAT
----- Original Message -----
From: "Chad Nelson"
Sent: Sunday, April 27, 2025 10:47:58 AM
Subject: [repeater-builder] Filter recommendation for DC fan motor
interference to echo Link.
> Hi everyone, I just installed a small DC fan to cool my Link radio
and notice when echo Link is active I get a wine on the signal going
into the controller for my echo link. Don't get this when repeater is
transmiting on its own. Any good filter recommendations to eliminate
this out?
> Chad Nelson WI9HF/WRPL979
> Janesville Wisconsin
> 608-754-8671
> Send from my spectrum iPhone 16.
>
>
>
>
>
>
--
Untitled Document
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Re: Filter recommendation for DC fan motor interference to echo Link.
The problem is your fan of course. I looked and can't find my information on it, but someone on here will probably have it. Panasonic make a line of fans that won't make electrical noise. I have fans for cooling one of my GM300 radios. It made noise. I tried everything, including running the fans on a battery, still had the noise. Just getting induced in the air. Finally I decided rather than to fight it, that I know when the fans come on and are working.
Mick - W7CAT
toggle quoted message
Show quoted text
----- Original Message ----- From: "Chad Nelson" To: repeater-builder@groups.io Sent: Sunday, April 27, 2025 10:47:58 AM Subject: [repeater-builder] Filter recommendation for DC fan motor interference to echo Link. Hi everyone, I just installed a small DC fan to cool my Link radio and notice when echo Link is active I get a wine on the signal going into the controller for my echo link. Don't get this when repeater is transmiting on its own. Any good filter recommendations to eliminate this out? Chad Nelson WI9HF/WRPL979
Janesville Wisconsin
608-754-8671
Send from my spectrum iPhone 16.
-- Untitled Document
|
PacParts sells the molex plug with the bumper wire.
Les Keegan? N4LPK?
On Sunday, April 27, 2025 at 10:51:24 AM EDT, Joel W6BQD via groups.io <berger.je@...> wrote:
The Service Manual is on RB. The rear panel 15 pin Molex connector is for attaching an external (KES-4, etc) speaker. If the supplied jumpered male Molex is missing, the previous user had an external speaker. With the jumpered plug missing, the audio output path is open, there is no audio from the internal speaker. Either jumper the open connector or attach an external speaker. It is not software controlled. No jumpered plug, no front panel speaker output.
Pin 9 & 12 jumpered. See page 54 of the TKR-850 Service manual on the RB site.
Joel Berger W6BQD
Just in case you are not a vet with the 850, is there a molex plug in the connector under the transmit coax connector? On my Kenwoods it has to be there with 2 pins jumpered for the speaker to work.? Don’t know if all configs need it but it took me a day to figure out that mine did. ? 73 Mike ? ? On 2025-04-26 11:50 p.m., Mike Sullivan via wrote: I have read it and programmed both a 70cm and a GMRS pair to test out. Both yield the same result, as stated above.
No audio at all. The antennas that the repeater and my base station are connected to are literally right next to each other, so there should be no problems at all.
Will be taking it to a friend to diagnose, just wanted to ask before I do so. ?
<-- What is the exact model of this 850, is it a version 1 or version 2 repeater? - reason for asking is that there was a design issue with earlier V1's (floating inputs on the DSP chip), which caused the 3.3V regulator (I think!) to fold, thus the audio amp having insufficient supply voltage. Despite this, you can also check for discriminator noise (with no RF signal applied) at pin 10 of the DB25, and once you inject a signal, you should see activity on this pin.? I would use a HT not a base station with antenna's so close! The other question is how far off from the original RX frequency are you? - the internal BPF has a 3dB BW of abut 10MHz:
 ? You will probably need to re-tune the RX (eventually), but for now, start with checking for noise and any sign of a signal on pin 10 of the rear DB25. ? <Credit to Jeff, WN3A for tutoring me on this stuff!>. ? Cheers, Ramesh, VA3UV, WA3UV ?
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Re: Help with out of range programming a Motorola GP300
"If the radio has the proper range . . ."
Then there is no need to do anything but program it as you normally would. What he is trying to do is program some radios that are NOT in the proper range. And again, I don't think the shift method will work to bring the frequency higher.
Mick - W7CAT
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----- Original Message ----- From: "Freddie Mac-KD5FMU via groups.io" To: repeater-builder@groups.io Sent: Sunday, April 27, 2025 10:01:42 AM Subject: Re: [repeater-builder] Help with out of range programming a Motorola GP300 Howdy,
If the radio has the proper range just hold down o the shift key while typing in the frequency but let off the shift key when typing the middle decimal. The press shift again when you type in the reminder of the frequency after the decimal then hit TAB and your frequency should display correctly. If it will not accept those frequencies, it will tell you.
Hope this helps
73
DE KD5FMU
--
Fred "Freddie Mac" McGuire - KD5FMU
Henryetta, OK
-- Untitled Document
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Filter recommendation for DC fan motor interference to echo Link.
Hi everyone, I just installed a small DC fan to cool my Link radio and notice when echo Link is active I get a wine on the signal going into the controller for my echo link. Don't get this when repeater is transmiting on its own. Any good filter recommendations to eliminate this out?
Chad Nelson WI9HF/WRPL979
Janesville Wisconsin
608-754-8671
Send from my spectrum iPhone 16.
|
Re: PD526 Duplexer Tuning
I ditto that. Every 526 I have tuned was done by individually tuning each cavity as per the instructions (there's more than one version of that) and then re-connect and each has been right on the money. First one in the 80's was done with a Measurements signal generator and Yaesu 708 portable as the receiver. Zero desense even with a GaAs FET preamp though it had its own preselector.
?
These are my preferred duplexers by far.?
GeorgeC W2DB
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Re: Help with out of range programming a Motorola GP300
Howdy,
If the radio has the proper range just hold down o the shift key while typing in the frequency but let off the shift key when typing the middle decimal. The press shift again when you type in the reminder of the frequency after the decimal then hit TAB and your frequency should display correctly. If it will not accept those frequencies, it will tell you.
Hope this helps
73
DE KD5FMU
--
Fred "Freddie Mac" McGuire - KD5FMU
Henryetta, OK
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KB9LFZ
Chris Boone WB5ITT
nh6bf
Mike Besemer - WM4B
Freddie Mac-KD5FMU